ﻻ يوجد ملخص باللغة العربية
The Cosmic Axion Spin Precession Experiment (CASPEr) seeks to measure oscillating torques on nuclear spins caused by axion or axion-like-particle (ALP) dark matter via nuclear magnetic resonance (NMR) techniques. A sample spin-polarized along a leading magnetic field experiences a resonance when the Larmor frequency matches the axion/ALP Compton frequency, generating precessing transverse nuclear magnetization. Here we demonstrate a Spin-Exchange Relaxation-Free (SERF) magnetometer with sensitivity $approx 1~{rm fT/sqrt{Hz}}$ and an effective sensing volume of 0.1 $rm{cm^3}$ that may be useful for NMR detection in CASPEr. A potential drawback of SERF-magnetometer-based NMR detection is the SERFs limited dynamic range. Use of a magnetic flux transformer to suppress the leading magnetic field is considered as a potential method to expand the SERFs dynamic range in order to probe higher axion/ALP Compton frequencies.
We present calculations of spin-relaxation rates of alkali-metal atoms due to the spin-axis interaction acting in binary collisions between the atoms. We show that for the high-temperature conditions of interest here, the spin relaxation rates calcul
We report on the use of radio-frequency optical atomic magnetometers for magnetic induction tomography measurements. We demonstrate the imaging of dummy targets of varying conductivities placed in the proximity of the sensor, in an unshielded environ
We demonstrate that spin-exchange dephasing of Larmor precession at near-earth-scale fields is effectively eliminated by dressing the alkali-metal atom spins in a sequence of AC-coupled 2-pi pulses, repeated at the Larmor precession frequency. The co
Ions confined using a Paul trap require a stable, high voltage and low noise radio frequency (RF) potential. We present a guide for the design and construction of a helical coil resonator for a desired frequency that maximises the quality factor for
We present a magnetometer based on optically pumped Cs atoms that measures the magnitude and direction of a 1 $mu$T magnetic field. Multiple circularly polarized laser beams were used to probe the free spin precession of the Cs atoms. The design was